Cryosurgery is commonly used in the practice of dermatology to treat various benign and malignant neoplasms and lesions of the skin. The equipment for treating patients with cryosurgery is currently cumbersome, expensive, and difficult to control. Additionally the refrigerants such as dry ice and liquid nitrogen are relatively unavailable, difficult to store and sometimes dangerous to use. This project will build on the successful findings of a Phase I research, that of using electronic semiconductors to generate the cryogenic temperatures necessary for cryosurgery procedures. The hand-held device will eliminate the need for compressed gasses, while giving positive control. Also, because solid state electronics lends itself to miniaturization, this research is expected to show that cryosurgical devices for use with various endoscopes will be possible. The cost to manufacture and distribute the product should be less than a three-year supply of other cryogens, and running power cost less than a dollar per day. The low cost should make the cryosurgical procedure more available to physicians both domestic and foreign, while helping reduce the cost of health care. Accurate temperature control will make possible research in cell destruction never before possible.